Certain asymmetric 1,3-cycloaddition reactions using N-benzyl-N-(methoxymethyl)trimethylsilylmethylamine (NBNMMA, compound (4) of Scheme 1 below) to produce cis-substitution have been reported. Rispens, et al. (Tetrahedron: Asymmetry, 5:607-624 (1994)) disclosed the addition of NBNMMA to 5-(R)-menthyloxy-2(5H)-furanone to produce a cis-fused pyrrolidinofuranone ring system, alleging the use of the latter as a precursor of cis-pyrrolidine compounds. Williams, et al. (Tetrahedron Lett., 33:6755-6758 (1992)) disclosed addition of NBNMMA to an exo-methylene group of a morpholin-2-one compound (an a,b-unsaturated lactone) to produce a spiro-pyrrolidine precursor to S-(-)-cucurbitine. Fray, et al. (Tetrahedron. Lett. 33:3575-3578 (1992)) disclosed addition of NBNMMA to non-racemic, unsaturated bicyclic lactams to produce pyrrolidine-cis-fused lactams. Wee (J. Chem. Soc., Perkin Trans., 1:1363-1364 (1989)) disclosed addition of NBNMMA to homochiral a,b-unsaturated esters and lactones to produce cis-substituted pyrrolidine compounds.
However, the use of removable chiral oxazolidinone compounds as auxiliary moieties to assist in stereodirection of NBNMMA in 1,3-cycloaddition reactions has not been disclosed. It would be desirable to have an improved and efficient process for the preparation of the cis- and trans-3-amino-4-substituted pyrrolidine compounds which may be utilized as intermediates in the preparation of suitably 7-substituted quinolone or 8-substituted 2-pyridone antibiotic compounds represented by the formula. ##STR4## wherein the substitutent 3-aminopyrrolidine at the 8-position exemplifies the chiral 3-aminopyrrolidine substituent at the 8-position.